Answer:
Jan. 5
Dr Account Receivable $4,000
Cr Sales $4,000
(to record sales to Rian)
Feb. 2
Dr Promissory note Receivable $4,000
Cr Account Receivable $4,000
(to record acceptance of Rian company's note)
Feb. 12
Dr Promissory note Receivable $12,000
Cr Sales $12,000
(to record sales to Cato company through acceptance its notes)
Feb. 26
Dr Account Receivable $5,200
Cr Sales $5,200
(to record sales to Malcolm)
Apr. 5
Dr Promissory note Receivable $5,200
Cr Account Receivable $5,200
( to record acceptance of Malcolm notes)
Apr. 12 ( assume Cato's note is collected)
Dr Cash $12,200
Cr Promissory note Receivable $12,000
Cr Interest Income $200
(to record the collection of Cato's note)
June. 2 ( assume Rian's note is collected)
Dr Cash $4,120
Cr Promissory note Receivable $4,000
Cr Interest Income $120
(to record the collection of Rian's note)
Jul. 5
Dr Cash $5,304
Cr Promissory note Receivable $5,200
Cr Interest Income $104
(to record the collection of Malcolm's note)
Explanation:
The calculation of Interest income from the Notes of the three companies as followed:
Rian: 4,000 x 9% x 4/12 = $120
Cato: 12,000 x 10% x 2/12 = $200
Malcolm: 5,200 x 8% x 3/12 = $104.
Further explanation has been put as description under each journal entries listed above.
Cost of goods sold is not included for each sales entries as guided in the question.
and 
is that the word management means to manage something carefully and good. And the word motivation is to motivate someone to do something weather good or bad.
